U.S. patent number 10,054,567 [Application Number 15/005,137] was granted by the patent office on 2018-08-21 for multi-layer ultrasound imagers.
This patent grant is currently assigned to The Boeing Company. The grantee listed for this patent is The Boeing Company. Invention is credited to Gary E. Georgeson, Tyler Holmes, Jeffrey R. Kollgaard.
United States Patent |
10,054,567 |
Georgeson , et al. |
August 21, 2018 |
Multi-layer ultrasound imagers
Abstract
Systems and methods for multi-layer ultrasonic imaging are
provided. One embodiment is an apparatus that includes linear
ultrasonic transducers that are each configured to conduct
electricity across their length. The apparatus includes a first
planar layer that comprises a first set of the transducers arranged
in parallel. The apparatus also includes a second planar layer that
comprises a second set of the transducers arranged in parallel, and
that is oriented such that each transducer of the second set
overlaps at least two transducers of the first set. Furthermore,
the apparatus includes a third planar layer that comprises a third
set of the transducers arranged in parallel, and that is oriented
such that each transducer of the third set overlaps at least two
transducers of the first set and at least two transducers of the
second set.
Inventors: |
Georgeson; Gary E. (Tacoma,
WA), Holmes; Tyler (Seattle, WA), Kollgaard; Jeffrey
R. (Seattle, WA) |
Applicant: |
Name |
City |
State |
Country |
Type |
The Boeing Company |
Chicago |
IL |
US |
|
|
Assignee: |
The Boeing Company (Chicago,
IL)
|
Family
ID: |
59360334 |
Appl.
No.: |
15/005,137 |
Filed: |
January 25, 2016 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170212083 A1 |
Jul 27, 2017 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01N
29/043 (20130101); G01N 29/221 (20130101); G01N
29/07 (20130101); G01N 29/069 (20130101); G01N
29/38 (20130101); G01N 29/2437 (20130101); G01N
29/262 (20130101); G01N 2291/106 (20130101); G01N
2291/103 (20130101) |
Current International
Class: |
G01N
29/06 (20060101); G01N 29/26 (20060101); G01N
29/38 (20060101); G01N 29/04 (20060101); G01N
29/07 (20060101); G01N 29/22 (20060101); G01N
29/24 (20060101) |
Field of
Search: |
;73/598,632,641,642
;310/322,334,336,367,368 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Phased Array Ultrasounds,
https://en.wikipedia.org/wiki/Phased_array_ultrasonics, Jan. 8,
2016. cited by applicant .
U.S. Appl. No. 13/928,870, filed Jun. 27, 2013, Robert B. Greegor,
Richard H. Bossi, John Z. Lin, Hong H. Tat, Alan F. Stewart. cited
by applicant .
U.S. Appl. No. 14/049,974, filed Oct. 9, 2013, Gary E. Georgeson
Tacoma, WA (US), William Joseph Tapia Graham, WA (US), Michael D.
Fogarty Auburn, WA (US), Hong Hue Tat Redmond, WA (US), Richard H.
Bossi Renton, WA (US), Robert L. Carlsen. cited by applicant .
U.S. Appl. No. 14/797,462, filed Jul. 13, 2015, Tyler M. Holmes
Seattle, WA (US), Jeffrey R. Kollgaard Seattle, WA (US), Gary E.
Georgeson Tacoma, WA (US). cited by applicant .
U.S. Appl. No. 14/809,522, filed Jul. 27, 2015, Tyler M. Holmes
Seattle, WA (US), Jeffrey R. Kollgaard Seattle, WA (US), Gary E.
Georgeson Tacoma, WA (US). cited by applicant.
|
Primary Examiner: Shah; Manish S
Assistant Examiner: Miller; Rose M
Attorney, Agent or Firm: Duft Bornsen & Fettig LLP
Claims
The invention claimed is:
1. An apparatus comprising: linear ultrasonic transducers that are
each configured to conduct electricity across their length; a first
planar layer that comprises a first set of the transducers arranged
in parallel; a second planar layer that comprises a second set of
the transducers arranged in parallel, and that is oriented for each
transducer of the second set to overlap at least two transducers of
the first set; a third planar layer that comprises a third set of
the transducers arranged in parallel, and that is oriented for each
transducer of the third set to overlap at least two transducers of
the first set and at least two transducers of the second set; and a
controller that transmits an ultrasonic wave from a transmitting
transducer in the first planar layer, detects a returning
ultrasonic wave at a receiving transducer in the second planar
layer, detects the returning ultrasonic wave at a receiving
transducer in the third planar layer, and identifies a surface
location corresponding to an intersection of the receiving
ultrasonic transducers.
2. An apparatus comprising: linear ultrasonic transducers which are
arranged into at least three layers that are each rotated a
different angle with respect to each other about an axis that is
perpendicular to the layers; and a controller that is configured to
selectively control the transducers in each of the layers to
transmit and receive ultrasonic waves by: transmitting an
ultrasonic wave from a transmitting transducer in a first of the
layers, detecting a returning ultrasonic wave at a receiving
transducer in a second of the layers, detecting the returning
ultrasonic wave at a receiving transducer in a third of the layers,
and identifying a surface location corresponding to an intersection
of the receiving ultrasonic transducers.
3. The apparatus of claim 2, wherein: the controller is configured
to transmit an ultrasonic wave via an ultrasonic transducer of the
first of the layers, to detect a returning ultrasonic wave at a
receiving ultrasonic transducer of the second of the layers, detect
the returning ultrasonic wave at a receiving ultrasonic transducer
of the third of the layers; and identify a position corresponding
to an intersection of the receiving ultrasonic transducers.
4. The apparatus of claim 3 wherein: the controller is configured
to select a depth being imaged by the ultrasonic wave, and to gate
detection of the ultrasonic wave to a time period corresponding to
the depth.
5. The apparatus of claim 3 wherein: the controller is configured
to fire multiple ultrasonic transducers from the first layer in a
timed sequence to generate a directional ultrasonic wave.
6. The apparatus of claim 2 wherein: the ultrasonic transducers
comprise piezoelectric elements.
7. The apparatus of claim 2 wherein: the apparatus comprises three
layers, and the first of the layers, second of the layers, and
third of the layers are angled about the axis by thirty, sixty, and
ninety degrees, respectively.
8. The apparatus of claim 2 wherein: the controller is configured
to detect subsurface features in an object being imaged by the
ultrasonic wave, based on the identified position.
9. The apparatus of claim 2 wherein: each of the layers is
separated from other layers by an electrically insulating
interlayer that is transparent to ultrasonic waves.
10. A method comprising: transmitting an ultrasonic wave via a
transmitting linear ultrasonic transducer located within a first
layer of an ultrasonic imaging apparatus that is perpendicular to
an axis; detecting a returning ultrasonic wave at a receiving
ultrasonic transducer located within a second layer of an
ultrasonic imaging apparatus that is rotated a second angle about
the axis with respect to the first layer; detecting the returning
ultrasonic wave at a receiving ultrasonic transducer located within
a third layer of an ultrasonic imaging apparatus that is rotated a
third angle about the axis with respect to the first layer, wherein
the second angle and third angle differ; and identifying a surface
location corresponding to an intersection of the receiving
ultrasonic transducers.
11. The method of claim 10 wherein: transmitting the ultrasonic
wave comprises driving electric current through a piezoelectric
element of the ultrasonic transducer in the first layer.
12. The method of claim 10 further comprising: detecting a
subsurface feature in an object being imaged by the ultrasonic
wave, based on the identified position.
13. The method of claim 10 further comprising: recording a peak
amplitude for the returning ultrasonic wave at each of the
receiving transducers.
14. The method of claim 10 further comprising: selecting a depth
being imaged by the ultrasonic wave; and gating detection of the
ultrasonic wave to a time period corresponding to the depth.
15. The method of claim 10 further comprising: firing multiple
ultrasonic transducers from the first layer in a timed sequence to
generate a directional ultrasonic wave.
16. The method of claim 10 further comprising: detecting an angle
of a subsurface feature of an object being imaged by the ultrasonic
wave, by comparing the identified position to an expected
position.
17. A non-transitory computer readable medium embodying programmed
instructions which, when executed by a processor, are operable for
performing a method comprising: transmitting an ultrasonic wave via
a transmitting linear ultrasonic transducer located within a first
layer of an ultrasonic imaging apparatus that is perpendicular to
an axis; detecting a returning ultrasonic wave at a receiving
ultrasonic transducer located within a second layer of an
ultrasonic imaging apparatus that is rotated a second angle about
the axis with respect to the first layer; detecting the returning
ultrasonic wave at a receiving ultrasonic transducer located within
a third layer of an ultrasonic imaging apparatus that is rotated a
third angle about the axis with respect to the first layer, wherein
the second angle and third angle differ; and identifying a surface
location corresponding to an intersection of the receiving
ultrasonic transducers.
18. The medium of claim 17 wherein: transmitting the ultrasonic
wave comprises driving electric current through a piezoelectric
element of the ultrasonic transducer in the first layer.
19. The medium of claim 17 wherein the method further comprises:
detecting a subsurface feature in an object being imaged by the
ultrasonic wave, based on the identified position.
20. The medium of claim 17 wherein the method further comprises:
recording a peak amplitude for the returning ultrasonic wave at
each of the receiving transducers.
21. The medium of claim 17 wherein the method further comprises:
selecting a depth being imaged by the ultrasonic wave; and gating
detection of the ultrasonic wave to a time period corresponding to
the depth.
22. The medium of claim 17 wherein the method further comprises:
firing multiple ultrasonic transducers from the first layer in a
timed sequence to generate a directional ultrasonic wave.
Description
FIELD
The disclosure relates to the field of imaging, and in particular,
to ultrasonic imaging.
BACKGROUND
Ultrasonic imaging is utilized in a variety of fields in order to
detect hidden sub-surface features in objects. For example,
ultrasonic imaging may be used to identify the internal structure
of a multi-layer composite part. This provides a substantial
benefit by enabling the detection of hidden wrinkles,
delaminations, or other inconsistencies within the composite part.
In composite parts that are subject to substantial loads, or that
are mission critical (e.g., a wing of an aircraft), inspection
processes are particularly important because they allow for
inconsistencies to be detected.
While ultrasonic imaging is a feasible technique for detecting the
presence of wrinkles and other inconsistencies within a composite
part, current ultrasonic imaging equipment remains complex and
expensive. Thus, users continue to desire ultrasonic imaging
systems that are highly effective, yet also affordable.
SUMMARY
Embodiments described herein include ultrasonic imagers that are
capable of pinpointing the position of an ultrasonic wave that has
been reflected off of an object being imaged. These ultrasonic
imaging devices utilize multiple layers of transducers. The
transducers in each layer are parallel with respect to each other,
and each layer is rotated with respect to the other layers about an
axis. This means that the transducers in one layer cross over
transducers in other layers. Thus, the location of a returning
ultrasonic wave may be determined based on the location at which
detecting transducers in different layers intersect.
One embodiment is an apparatus that includes ultrasonic transducers
that are each configured to conduct electricity across their
length. The apparatus includes a first planar layer that comprises
a first set of the transducers arranged in parallel. The apparatus
also includes a second planar layer that comprises a second set of
the transducers arranged in parallel, and that is oriented such
that each transducer of the second set overlaps at least two
transducers of the first set. Furthermore, the apparatus includes a
third planar layer that comprises a third set of the transducers
arranged in parallel, and that is oriented such that each
transducer of the third set overlaps at least two transducers of
the first set and at least two transducers of the second set.
A further embodiment is an apparatus that includes ultrasonic
transducers which are arranged into layers that are each rotated a
different angle about an axis that is perpendicular to the layers.
The apparatus also includes a controller that is configured to
selectively control the transducers in each of the layers to
transmit and receive ultrasonic waves. For example, the controller
may transmit an ultrasonic wave via an ultrasonic transducer of a
first of the layers, detect a returning ultrasonic wave at a
receiving ultrasonic transducer of a second of the layers, detect
the returning ultrasonic wave at a receiving ultrasonic transducer
of a third of the layers, and identify a position corresponding to
an intersection of the receiving ultrasonic transducers.
Another embodiment is a method for ultrasonic imaging. The method
includes transmitting an ultrasonic wave via a transmitting
ultrasonic transducer located within a first layer of an ultrasonic
imaging apparatus that is rotated a first angle about an axis that
is perpendicular to the first layer. The method also includes
detecting a returning ultrasonic wave at a receiving ultrasonic
transducer located within a second layer of an ultrasonic imaging
apparatus that is rotated a second angle about the axis, and
detecting the returning ultrasonic wave at a receiving ultrasonic
transducer located within a third layer of an ultrasonic imaging
apparatus that is rotated a third angle about the axis. Further,
the method includes identifying a surface location corresponding to
an intersection of the receiving ultrasonic transducers.
Another embodiment is a non-transitory computer readable medium
embodying programmed instructions which, when executed by a
processor, are operable for performing a method. The method
includes transmitting an ultrasonic wave via a transmitting
ultrasonic transducer located within a first layer of an ultrasonic
imaging apparatus that is rotated a first angle about an axis that
is perpendicular to the first layer. The method also includes
detecting a returning ultrasonic wave at a receiving ultrasonic
transducer located within a second layer of an ultrasonic imaging
apparatus that is rotated a second angle about the axis, and
detecting the returning ultrasonic wave at a receiving ultrasonic
transducer located within a third layer of an ultrasonic imaging
apparatus that is rotated a third angle about the axis. Further,
the method includes identifying a surface location corresponding to
an intersection of the receiving ultrasonic transducers.
Other exemplary embodiments (e.g., methods and computer-readable
media relating to the foregoing embodiments) may be described
below. The features, functions, and advantages that have been
discussed can be achieved independently in various embodiments or
may be combined in yet other embodiments further details of which
can be seen with reference to the following description and
drawings.
DESCRIPTION OF THE DRAWINGS
Some embodiments of the present disclosure are now described, by
way of example only, and with reference to the accompanying
drawings. The same reference number represents the same element or
the same type of element on all drawings.
FIG. 1 is a diagram of ultrasonic imaging in an exemplary
embodiment.
FIG. 2 is a block diagram of an ultrasonic imager in an exemplary
embodiment.
FIGS. 3-4 illustrate transducers grouped into layers for an
ultrasonic imager in an exemplary embodiment.
FIG. 5 is a flowchart illustrating a method for operating an
ultrasonic imager in an exemplary embodiment.
FIGS. 6-7 are diagrams illustrating scenarios in which no
inconsistency is detected within an object being imaged.
FIGS. 8-9 are diagrams illustrating scenarios in which an
inconsistency is detected within an object being imaged.
FIG. 10 is a diagram illustrating detected variations in a wrinkle
in an object in an exemplary embodiment.
FIG. 11 is a flow diagram of aircraft production and service
methodology in an exemplary embodiment.
FIG. 12 is a block diagram of an aircraft in an exemplary
embodiment.
DESCRIPTION
The figures and the following description illustrate specific
exemplary embodiments of the disclosure. It will thus be
appreciated that those skilled in the art will be able to devise
various arrangements that, although not explicitly described or
shown herein, embody the principles of the disclosure and are
included within the scope of the disclosure. Furthermore, any
examples described herein are intended to aid in understanding the
principles of the disclosure, and are to be construed as being
without limitation to such specifically recited examples and
conditions. As a result, the disclosure is not limited to the
specific embodiments or examples described below, but by the claims
and their equivalents.
FIG. 1 is a diagram illustrating transmission and reflection of an
ultrasonic wave in an exemplary embodiment. As shown in FIG. 1, a
transmitted ultrasonic wave 102 is sent in a direction (Z) by an
ultrasonic imager 200 into a multi-layer composite part 150
comprising layers 151-156. When the transmitted ultrasonic wave
strikes a boundary 103 between layers 152 and 153 of part 150, a
returning ultrasonic wave 140 is generated. Depending on the
orientation of the boundary between the layers, returning
ultrasonic wave 104 may be displaced upon arrival at imager 200 by
some distance (.DELTA.). This distance of displacement, when
analyzed in combination with the depth (D) of the location being
imaged, may be used to extract a value (.theta.) indicating an
angle of a wrinkle at the location being imaged. In general, the
larger the value of (.DELTA.), the larger the value of (.theta.). A
higher value of (.theta.) indicates the presence of an
inconsistency that is more intense (e.g., "kinked" at a greater
angle with respect to its surroundings) within the layers of part
150.
Receivers/transducers that are being used to image the returning
ultrasonic wave 104 may be gated to acquire input only during a
range of times after the transmitted ultrasonic wave has been sent,
and may also be gated to only acquire input at a range of
amplitudes (e.g., in order to filter out noise). The range of times
chosen as gate values determines the depth that is being imaged
within part 150. Specifically, a range of times corresponding to a
longer period of time results in a deeper portion of object 150
being imaged by ultrasonic imager 200.
FIG. 2 is a block diagram of ultrasonic imager 200 in an exemplary
embodiment. Ultrasonic imager 200 includes multiple planar layers
(210, 220, 230) of linear transducers (e.g., 212, 222, 232). Each
layer includes transducers that are oriented parallel to each
other. For example, layer 210 includes transducers 212, 214, 216,
and 218, layer 220 includes transducers 222, 224, 226, and 228, and
layer 230 includes transducers 232, 234, 236, and 238. The
transducers (e.g., 212, 222, 232) in each layer are rotated with
respect to transducers (e.g., 212, 222, 232) in other layers, as is
illustrated in FIG. 3. The transducers (e.g., 212, 222, 232)
described herein comprise any suitable components capable of
transmitting and/or receiving ultrasonic waves. In one embodiment,
the transducers (e.g., 212, 222, 232) comprise linear piezoelectric
elements (e.g., piezoresistors) that vibrate in response to
receiving an ultrasonic wave, resulting in a detectable change in
current. Such piezoelectric elements may also be operated by
driving current through them, causing the piezoelectric elements to
vibrate and thereby transmit ultrasonic waves. Controller 250 is
configured to direct the operations of the various transducers
described herein (e.g., 212, 222, 232) as the transducers generate
and/or receive ultrasonic waves. Controller 250 may further be
operable to identify a surface location at ultrasonic imager 200
corresponding to the location of a detected ultrasonic wave.
Controller 250 may be implemented, for example, as custom
circuitry, as a processor executing programmed instructions, or
some combination thereof.
FIG. 3 illustrates an arrangement of transducers (e.g., 212, 222,
232) grouped into layers for ultrasonic imager 200 in an exemplary
embodiment. FIG. 3 illustrates that each layer (210, 220, 230) is
separated from the other layers along a direction (Z). The distance
between layers shown in FIG. 3 is exaggerated for purposes of
clarity. In embodiments where a substantial amount of vertical
distance separates the layers, controller 250 may adjust gating
parameters separately for each of the layers to ensure that each
layer images object 150 at the same depth. In a further embodiment,
the layers (210, 220, 230) may be separated by an electrically
insulating interlayer, in order to ensure that electric
interference does not result in noise or false signal detection
while ultrasonic imager 200 is being operated.
As shown in FIG. 3, each layer is rotated about the axis of
direction Z by a different value (e.g., .PHI.1, .PHI.2, .PHI.3).
Hence a transducer (212) in layer 210 will overlap at least one
transducer (222) in layer 220, and at least one transducer (232) in
layer 230. This cross-over between different transducers (e.g.,
212, 222, 232) is particularly beneficial in implementations where
the transducers (e.g., 212, 222, 232) are each implemented as a
linear piezoelectric element. In these cases, even though
individual transducers (e.g., 212, 222, 232) only provide
resolution on a "line by line" basis, the intersection of two
transducers (e.g., 222, 232) in different layers may be used to
determine the exact location at which a returning ultrasonic wave
was received at ultrasonic imager 200. The view shown in FIG. 4 is
a head-on view of ultrasonic imager 200 indicated by view arrows 4.
This view illustrates each of three layers utilized for ultrasonic
imager 200, as they are "stacked" on top of each other.
Illustrative details of the operation of ultrasonic imager 200 will
be discussed with regard to FIG. 5. Assume, for this embodiment,
that object 150 (e.g., a composite part for an aircraft wing or
fuselage) is being inspected for inconsistencies that are below the
surface of object 150. FIG. 5 provides a technique for detecting
not just the existence of inconsistencies within object 150, but
also quantifying the size of those inconsistencies.
FIG. 5 is a flowchart illustrating a method 500 for utilizing an
ultrasonic imager to detect inconsistencies in an object in an
exemplary embodiment. The steps of method 500 are described with
reference to ultrasonic imager 200 of FIG. 1, but those skilled in
the art will appreciate that method 500 may be performed in other
systems. The steps of the flowcharts described herein are not all
inclusive and may include other steps not shown. The steps
described herein may also be performed in an alternative order.
In step 502, controller 250 sends electrical current through a
transducer 212 in a first layer 210 of ultrasonic imager 200, which
causes transducer 212 to transmit an ultrasonic wave into object
150. Since controller 250 is driving current through transducer 212
to generate an ultrasonic wave, transducer 212 will not be used to
detect a returning ultrasonic wave.
The transmitted ultrasonic wave continues through object 150 until
it hits a location exhibiting a change in material properties, such
a border between layers of constituent material within object 150.
Upon hitting the location, a returning, reflected ultrasonic wave
is generated. The returning ultrasonic wave returns back towards
ultrasonic imager 200, but will be deflected in a direction if the
location was not flat/normal with respect to the transmitted
ultrasonic wave. The amount of deflection increases as the slope of
the location deviates from an expected, normal configuration. Thus,
the degree of deviation exhibited by a kink or wrinkle in object
150 may be quantified by determining an amount of deflection
applied to the returning ultrasonic wave.
To determine the location at which the returning ultrasonic wave
was received, controller 250 engages in a gated listening process
in steps 504-506. In step 504, controller 250 detects a returning
ultrasonic wave at a transducer 222 of layer 220, while in step
506, controller 250 detects a returning ultrasonic wave at a
transducer 232 of layer 230. In embodiments wherein ultrasonic
imager 200 utilizes piezoelectric transducers, the returning
ultrasonic wave will cause vibrations in the transducers (e.g.,
212, 222, 232) that result in a detectable change in resistance at
the transducer. In such an embodiment, the first transducer in a
layer that detects the returning ultrasonic wave (e.g., 222) may be
considered the detecting transducer for that layer.
In response to identifying the detecting transducer (e.g., 222,
232) at each of the other layers (e.g., layer 220 and layer 230),
controller 250 identifies a surface location at imager 200
corresponding to an intersection of the receiving ultrasonic
transducers (e.g., 222, 232) in step 508. This step may comprise
consulting data stored in memory indicating locations on the
surface of ultrasonic imager 200 occupied by each of the detecting
transducers (e.g., 222, 232), and then calculating an intersection,
or may comprise looking up a known surface location, based on the
identity of the two detecting transducers (e.g., 222, 232). This
surface location may then be output via a screen or display,
transmitted for further analysis, or further analyzed by controller
250.
If the surface location corresponds with/lines up with the
transducer 212 that originally generated the transmitted ultrasonic
wave, then controller 250 may determine that no substantial
inconsistency exists at the imaged depth underneath the
transmitting transducer. In contrast, if the surface location does
not align with the transmitting transducer, then the returning
ultrasonic wave has been deflected by some angle .theta. and an
inconsistency exists.
FIGS. 6-7 illustrate scenarios in which no inconsistency is
detected within an object being imaged. In these scenarios, the
returning ultrasonic wave has not been deflected away from the
transmitting transducer (e.g., 212). For example, FIG. 6
illustrates a transmitting transducer 612, and two detecting
transducers 622 and 632. In this example, the intersection 650 of
transducers 622 and 612 is co-located with transmitting transducer
612. Hence, controller 250 may conclude that no substantial
inconsistencies exist at the imaged depth and location. Similarly,
FIG. 7 illustrates a transmitting transducer 712, and two detecting
transducers 722 and 732. In this example, the intersection 750 of
transducers 722 and 712 is co-located with transmitting transducer
712.
FIGS. 8-9 illustrate scenarios in which an inconsistency is
detected within an object being imaged. In FIG. 8, transmitting
transducer 812 is not co-located with intersection 850 of detecting
transducers 822 and 832. Hence, the returning ultrasonic wave was
deflected at an angle .theta. (e.g., as shown in FIG. 2).
Similarly, in FIG. 9, transmitting transducer 912 is not co-located
with intersection 950 of detecting transducers 922 and 932. Note
that the intersection 950 is roughly parallelogram/diamond shaped
in this embodiment, corresponding to the shape of overlapping
portions of transducers 922 and 932.
In further embodiments, an ultrasonic imager may be used to
identify wrinkles and other inconsistencies within object 150, and
to quantify the nature of inconsistencies that exist underneath the
surface of object 150. In one embodiment, controller 250 engages in
further analysis to determine an angle of the detected
inconsistency. This calculation may be performed via trigonometric
functions based on the depth being imaged, and the distance between
the identified surface location and the transmitting transducer
(e.g., 212). For example, as shown in FIG. 1, controller 250 may
determine that the tangent of .theta. is equal to depth (D) divided
by the distance (.DELTA.), and may calculate .theta. based on this
relationship.
During operation, ultrasonic imager 200 may engage in multiple
cycles of transmission and detection of ultrasonic waves. By
transmitting ultrasonic waves from a different transducer in each
cycle (e.g., a different transducer in the same layer, or a
transducer in a different layer), controller 250 is capable of
mapping inconsistencies along object 150. Controller 250 may also
select a depth to be imaged, by gating the detection period used by
the various transducers discussed herein.
Controller 250 may further generate a map (e.g., a two dimensional
(2D) or three dimensional (3D) map, depending on whether different
depths are imaged) indicating the location and intensity of
inconsistencies within object 150, based on these measurements. In
this manner, off-angle reflections for individual strip "firings"
are collected and combined over time by controller 250 to map the
shape and intensity of inconsistencies within object 150. For
example, FIG. 10 illustrates off-angle reflections caught during a
time-of-flight period that are above a gated amplitude. In FIG. 10,
parallelogram/diamond shaped locations 1002 correspond with the
intersections of transducers that detect the returning ultrasonic
wave at a first time, while locations 1004 correspond with the
intersections of transducers that detect the returning ultrasonic
wave at a second time fractionally later than the first time. Since
locations 1002 and 1004 are not co-located with transmitting
transducer 1012, they illustrate a wrinkle 1000 of varying
intensity/angle along the length of transmitting transducer
1012
In yet a further embodiment, ultrasonic waves/beams are "steered"
by controller 250 time-sequencing transmissions from adjacent
transducers in the same layer (e.g., 212 and its neighbors) to
collect reflection angles at various depths within object 150. In
this embodiment, beam steering techniques (such as those used for
phased array antennae) may be used to map wrinkle shape and
intensity in composites and perform swept inspections of metals. In
short controller 250 may fire multiple ultrasonic transducers from
the first layer 210 in a timed sequence to generate a directional
ultrasonic wave.
In yet another embodiment, controller 250 transmits ultrasonic
waves/beams at one angle and expects receipt of a returning
ultrasonic wave at an expected angle, distance and time. In this
embodiment, variations in intensity and return location (from their
expected values) may be used to identify and map wrinkles within
object 150.
Although only three layers of transducers (210, 220, 230) are
illustrated with respect to the discussion above that are each
rotated 60.degree. apart, any suitable number of layers, and/or
angle between layers, may be utilized to engage in the ultrasonic
imaging techniques described herein.
Referring more particularly to the drawings, embodiments of the
disclosure may be described in the context of an aircraft
manufacturing and service method 1100 as shown in FIG. 11 and an
aircraft 1102 as shown in FIG. 12. During pre-production, exemplary
method 1100 may include specification and design 1104 of the
aircraft 1102 and material procurement 1106. During production,
component and subassembly manufacturing 1108 and system integration
1110 of the aircraft 1102 takes place. Thereafter, the aircraft
1102 may go through certification and delivery 1112 in order to be
placed in service 1114. While in service by a customer, the
aircraft 1102 is scheduled for routine maintenance and service 1116
(which may also include modification, reconfiguration,
refurbishment, and so on). The inventive techniques and systems
described herein may further be implemented, for example, as a part
of material procurement 1106 (e.g., in order to quantify the
quality of materials being procured), as a part of component and
subassembly manufacturing (e.g., for purposes of quality control),
in system integration 1110, during certification and delivery 1112
to facilitate quality control, in service 1114 to examine operating
aircraft, and/or in maintenance and service 1116
Each of the processes of method 1100 may be performed or carried
out by a system integrator, a third party, and/or an operator
(e.g., a customer). For the purposes of this description, a system
integrator may include without limitation any number of aircraft
manufacturers and major-system subcontractors; a third party may
include without limitation any number of vendors, subcontractors,
and suppliers; and an operator may be an airline, leasing company,
military entity, service organization, and so on.
As shown in FIG. 12, the aircraft 1102 produced by exemplary method
1100 may include an airframe 1118 with a plurality of systems 1120
and an interior 1122. Examples of high-level systems 1120 include
one or more of a propulsion system 1124, an electrical system 1126,
a hydraulic system 1128, and an environmental system 1130. Any
number of other systems may be included. Although an aerospace
example is shown, the principles of the invention may be applied to
other industries, such as the automotive industry.
Apparatus and methods embodied herein may be employed during any
one or more of the stages of the production and service method
1100. For example, an ultrasonic imager may be utilized during
component and subassembly manufacturing 1108 to verify part
integrity, in system integration 1110, certification and delivery
1112, and/or during maintenance and service 1116. Also, one or more
apparatus embodiments, method embodiments, or a combination thereof
may be utilized during the production stages 1108 and 1110, for
example, by substantially expediting assembly of or reducing the
cost of inspecting an aircraft 1102. Similarly, one or more of
apparatus embodiments, method embodiments, or a combination thereof
may be utilized while the aircraft 1102 is in service, for example
and without limitation, to maintenance and service 1116.
In one embodiment, ultrasonic imager 200 is utilized to inspect a
portion of airframe 118 that was manufactured during component and
subassembly manufacturing 1108. Ultrasonic imager 200 may be used
to perform further inspections in system integration 1110, and in
maintenance and service 1116, when object 150 may be discarded and
replaced with a newly manufactured part 1116.
Any of the various computing elements shown in the figures or
described herein may be implemented as hardware, software operating
via a processor, firmware, or some combination of these. For
example, an element may be implemented as dedicated hardware.
Dedicated hardware elements may be referred to as "processors",
"controllers", or some similar terminology. When provided by a
processor, the functions may be provided by a single dedicated
processor, by a single shared processor, or by a plurality of
individual processors, some of which may be shared. Moreover,
explicit use of the term "processor" or "controller" should not be
construed to refer exclusively to hardware capable of executing
software, and may implicitly include, without limitation, digital
signal processor (DSP) hardware, a network processor, application
specific integrated circuit (ASIC) or other circuitry, field
programmable gate array (FPGA), read only memory (ROM) for storing
software, random access memory (RAM), non-volatile storage, logic,
or some other physical hardware component or module.
Also, an element may be implemented as instructions executable by a
processor or a computer to perform the functions of the element.
Some examples of instructions are software, program code, and
firmware. The instructions are operational when executed by the
processor to direct the processor to perform the functions of the
element. The instructions may be stored on storage devices that are
readable by the processor. Some examples of the storage devices are
digital or solid-state memories, magnetic storage media such as a
magnetic disks and magnetic tapes, hard drives, or optically
readable digital data storage media.
Although specific embodiments are described herein, the scope of
the disclosure is not limited to those specific embodiments. The
scope of the disclosure is defined by the following claims and any
equivalents thereof.
* * * * *
References